• 열처리공학회지
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• 제17권1호
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• pp.29-35
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• 2004

The effect of low tempering in a temperature range of $150{\sim}400^{\circ}C$ on corrosion resistance in 420J2 stainless steel austenitized at $1000^{\circ}C$ was investigated by the application of salt spray test, electrochemical pitting test in 3.5% NaCl solution and DL-EPR test for intergranular corrosion in 0.5M $H_2SO_4$+0.01M KSCN solution. In salt spray test, good corrosion resistance was obtained in a tempering temperature range of $150{\sim}250^{\circ}C$. Pitting potential was increased to the tempering temperature of $250^{\circ}C$, but decreased with the increase of temperature up to $400^{\circ}C$ And it was thought that the degradation of pitting corrosion resistance showed at the tempering temperature of around $400^{\circ}C$ was due to the precipitation of $Cr_7C_3$ of $M_7C_3$ type. The degree of sensitization showed increasing tendency with the increase of tempering temperature, and also Cr depletion phenomena were observed in the vicinity of grain boundary.

• International Journal of Concrete Structures and Materials
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• 제5권2호
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• pp.87-96
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• 2011

Many studies have been performed on steel fiber-reinforced normal/high-strength concrete (SFRC, SFRHC) for years, which is to improve some of the weak material properties of concrete. Most of equations for material strengths of SFRHC, however, were proposed based on relatively limited test results. In this research, therefore, the material test results of SFR(H)C were extensively collected from literature, and material tests have conducted on SFR(H)C; compressive strength tests, splitting tensile tests, and modulus of rupture tests. Based on the extensive test data obtained from previous studies and this research, a database of SFR(H)C material strengths has been established, and improved equations for material strengths of SFR(H)C were also proposed. Test results showed that both the splitting tensile strength and the modulus of rupture of SFR(H)C increased as the volume fraction of steel fiber increased, while the effect of the steel fiber volume fraction on the compressive strength of SFR(H)C were not clearly observed. The proposed equations for the splitting tensile strength and the modulus of rupture of SFR(H)C showed better results than the previous equations examined in this study in terms of not only accuracy but also safety/reliability.

• 한국주조공학회지
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• 제11권4호
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• pp.323-330
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• 1991

The relationships between the microstructure changes, retained austenite volume and elevated temperature tensile properties of Mo-Ni-Cu ADI corresponding to various austempering temperatures and time were investigated, After the $250^{\circ}C$ tensile test for the test piece austempered at $270^{\circ}C$ the accicular bainite structure was observed blunted under room temperature microscope. In the case of $370^{\circ}C$ austempering, the feathery bainite lath spacing was observed broadened. But after the $450^{\circ}C$ tensile test, bainitic features could not be observed. As the testing temperature increased, retained austenite volume tested at room temperature decreased. Especially, after the $450^{\circ}C$ tensile test retained austenite volume approached nearly to zero. A little higher tensile properties appeared at $250^{\circ}C$ testing than those at room temperature.

• 융합보안논문지
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• 제13권4호
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• pp.33-39
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• 2013

소프트웨어 개발을 성공적으로 수행하기 위하여서 유닛 테스팅은 아주 필수 불가결한 요소이다. Python, Java, C# 등의 현대 컴퓨터 개발 언어에서는 유닛 테스팅을 용이하게 하기 위하여 다양한 기능을 제공하고 있다. 하지만, C++ 언어에 있어서는 워낙 많은 프레임워크를 제공하고 있는 관계로, 유닛 테스팅을 위한 프레임워크 선택이 결코 용이하지 않다. 이 논문에서는 C++ 언어에서의 유닛 테스팅을 위한 프레임워크를 집약된 test runner와 분리된 test runner의 두 그룹으로 나눠서 고찰하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.495-496
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• 2007

An Over Current Relayng algorithm using 80c196kc micro processor was realized in this paper. This OCR Algorithm was verified with simulated fault signal. The fault signal was made by EMTP and realized by DOBLE to compare H/W test with S/W test. This simulations showed similar result between H/W and S/W test.

• 한국항해항만학회지
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• 제34권8호
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• pp.623-628
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• 2010

현재 모형선을 이용한 선형성능 검증설비는 예인수조와 회류수조 두설비가 주로 이용된다. 이들 설비는 주로 저속 대형선박을 위해 기법들로 소형 고속어선 및 고속레저선박의 저항성능 평가를 수행하기에 전차의 속도와 유속이 목표속도에 미치지 못해 어려움이 존재한다. 따라서 고속 선박의 저항성능 평가를 위해 새로운 기법 정립 연구가 필요하다. 이에 고속선의 저항성능 시험을 위해 실제 해상에서 선박을 이용한 모형시험을 고안하고 측정시스템을 구성하였다. 시스템구성은 총 8개의 파트로 구성되어 있으며, 시스템 검증을 위해 C.W.C에서 저속선의 모형을 이용하여 시험을 수행하여 시스템 적용 가능성을 검증하였다. 또한 실제 해상에서 고속선 모형선을 이용하여 시험을 수행하였으며, 이 결과를 CFD해석 결과와 비교하여 실해상 모형시험 방법의 가능성을 확인 하였다.

• 대한가정학회지
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• 제42권12호
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• pp.69-76
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• 2004

The purpose of this study was to investigate the colorfastness of cotton and silk fabric dyed with extract of Lotus leaf princeps. The experimental items were classified into mordanting treatments, fabric components and kind of mordants. The experimental test was done by laundering, abrasion(dry/wet), perspiration(acid/alkali) , light fastness, color difference by C.C.M(computer color matching) system and K/S test. The summarized findings resulting from the experiment and investigation are as follows: In the C.C.M and K/S test on mordanting method and kind of fabrics, co-mordanting treatment method and protein fabric (silk) were the most effective. Especially, Fe mordanting treatment was higher than Al, Cu, Cr and none-mordanting. In colorfastness on the mordants, perspiration and laundering fastness showed high grade (4-5) but grades of perspiration(2-3/4) and light fastness(1-3) were low.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2313-2315
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• 2003

This paper presents the development methods which Samsung GPS baseband chip is called S3E4510X. Specification of S3E4510X and design methodology of baseband architecture is presented with a study of their effects. Also GPS core block and software are described in detail. We designed and implemented the test board with RF module for evaluating performance via static test dynamic test and each performance factors using live signal and CPS simulator. Test results show that our development GPS baseband chip have effectively performance for mobile handset Location Based Service (LBS) and its practical use for navigation.

• 열처리공학회지
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• 제21권3호
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• pp.150-156
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• 2008

The effects of austenitizing temperature in a range of $1000{\sim}1150^{\circ}C$ on the corrosion resistance in 420J2 stainless steel tempered at $150^{\circ}C$ were investigated by an electrochemical uniform corrosion test in a solution of 0.5M $H_2S0_4$. Pitting test and DL-EPR test for intergranular corrosion were carried out in a solution of 3.5% NaCl and 0.5M $H_2S0_4$ + 0.01 M KSCN respectively. In uniform corrosion test, specimens austenitized below $1100^{\circ}C$ showed similar corrosion current density and passive current density, whereas specimens austenitized at $1150^{\circ}C$ showed a little higher values. Pitting potential slightly increased with an increase of austenitizing temperature. The degree of sensitization, DOS, also slightly increased with an increase of austenitizing temperature, reaching the highest degree at $1150^{\circ}C$. It was expected that the increase of DOS was due to the larger grain size rather than the dissolved precipitates in the matrix.

• 보건행정학회지
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• 제26권3호
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• pp.207-218
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• 2016

Background: This study was performed to identify factors associated with the utilization of tests for diabetes complication and hemoglobin A1c (HbA1c) among diabetes patients in Jeollanam-do, Korea. Methods: The study subjects were 2,310 diabetes patients participated in 2014 community health survey in Jeollanam-do, Korea. Dependent variables were the utilizations of fundus examination, microalbuminuria test, and HbA1c test. The used statistical analysis methods were chi-square test and hierarchical regression analysis with weight in consideration of complex sample design. Results: The utilization rates of fundus examination, microalbuminuria test, and HbA1c test were 25.8%, 27.4%, and 12.3%, respectively. In the results of hierarchical regression, fundus examination was significantly related to age, education level in predisposing factors, residential area in enabling factors and recognition of blood sugar, drug therapy, and subjective health status in need factors. Microalbuminuria examination was significantly related to monthly income, residential area in predisposing and health screening, recognition of blood sugar, drug therapy, diabetic education, number of chronic disease, and subjective health status in need factors. HbA1c examination was significantly related to age, education level, marital status in predisposing factors, residential area in enabling factors and drinking, recognition of blood sugar, drug therapy, and diabetic education in need factors. Conclusion: The results of this study were shown that perception of their disease seriousness, education about diabetes management, and accessibility of tests were important to utilization of test for diabetes complication and HbA1c. It might be necessary to the develop and strength strategies for enhancing the utilization of tests for diabetes complication and management in diabetes patients.